Steel Grades

An unfavorable combination of H2S dissolved in water, low pH, susceptible structure and high tensile loads could cause cracks to occur in steel pipes, and propagate until failure.

Our sour service grades (SS) are designed to prevent sulfide stress cracking (SSC) failures when used in the appropriate domain.

The improved resistance to SSC is obtained through a specific design of the steel chemistry and a tight control of microstructure and mechanical properties. Only state-of-the-art facilities can achieve this result.

Our SS steel grades are available in minimum yield strength ranging from 80 up to 125 ksi, thanks to our high collapse and sour service (HS) series adding enhanced collapse resistance.

Mild sour steel grades are specifically developed to meet customer's needs for sour environments of limited severity.

For well environments presenting medium severity combination of low pH and H2S content, improved resistance to SSC may be needed together with high mechanical resistance.

When cost-effectiveness is an important factor, mild sour grades are a sustainable alternative.

Our micro-alloyed 3% Cr steel grades for critical service (CS) maintain chromium in solid solution to increase strength and mechanical performance.

Used alone or in combination with a proper inhibition program, CS grades are an improved solution in sweet (CO2) corrosion environments also for water injection in mature fields, tolerating a limited amount of CO2 in milder conditions than the ones requiring martensitic stainless steels (Cr13).

In addition to uniform external pressures, the reservoir can exert high pressures due to ground movements or saline strata, subjecting pipes to extreme localized external pressure.

High collapse performance is achieved through a taylor-made manufacturing process, with special focus on both geometrical parameters and mechanical properties (yield and tensile strength).

On top of it, we developed our own proprietary model to predict the collapse rate based on a large distribution of collapse testing.

Our HC Series is available in minimum yield strengths ranging from 80 to 140 ksi with higher guaranteed collapse pressure than the one determined by API 5CT/ISO 11960 of equivalent grade.

Improved collapse grades are developed on the basis of API steel grades with enhanced collapse performance.

They are available in minimum yield strength of 110 and 125 ksi. In order to enhance the performance in internal yield pressure, these grades can be manufactured with controlled yield strength (ICY grades).

As well depth increases, a combination of high pressures and elevated temperatures defines the use of high strength materials. We offer not only a very high material strength with a good fracture toughness, but also a mild sour resistance achieved by a controlled yield and limited maximum hardness.

A very strict heat treatment furnace control guarantees a good ductility distribution, improved fracture toughness and homogeneous yield, in order to achieve a limited maximum hardness. Also, upon request, we can apply a tailored process route to improve collapse rating on these steel grades.

As yield strength increases, carbon steel tends to become more brittle: it may fail under loads, even below its minimum yield strength.

We designed steel composition and heat treatment of deep well (DW) grades targeting an optimized yield strength / toughness trade-off: high yield strength and good ductility are granted, together with fracture toughness proved by Charpy testing at specific temperatures.

Our deep well grades are available in minimum yield strengths ranging from 135 to 150 ksi.

A condition of high CO2 partial pressure, together with critical combinations of temperature, presence of chlorides and H2S, produces in steel high corrosion rates and a tendency to cracking. We manufacture 13% Cr alloys, martensitic stainless steels for oil and gas operations in highly corrosive environments, including presence of H2S, where carbon steel tubulars cannot be used.

Supermartensitic stainless steels are suitable for applications that require better performance than 13Cr steels in terms of corrosion resistance and combination of properties required in specific environments: designed on the recommendations of NACE MR075 / ISO 15156 with an accurate material selection, they are manufactured according to the same specifications of other corrosion resistant alloys.

Corrosion resistant alloys (CRA) with high contents of chromium (Cr), molybdenum (Mo) and nickel (Ni) are needed for aggressive environments.

We offer duplex, superduplex and austenitic stainless steels to face corrosion in different critical regions defined by combinations of the following factors: presence of CO2 and H2S corrosive gases, high downhole temperatures, low pH and chlorides.

Thanks to our alliance with Sandvik and the support of other qualified suppliers, we can provide our entire connections dimensional range in CRA materials according to the API 5CRA and ISO 13680 international standards.